(Cyclic Organic Silicon-based Compound)
Numerous compounds are known as halogenosilanes and alkoxysilanes, having a protected alkali-soluble group. The protected alkali-soluble group includes carboxyl group and protected hydroxyl group in phenol, catechol (for example in Patent Document 1 and Patent Document 2) or alcohol.
Halogenosilanes and alkoxysilanes, having an alkali-soluble group are useful as a starting material for lithographic material, organic-inorganic hybrid material and the like.                [Patent Document 1] JP-A-2002-249493        [Patent Document 2] JP-A-2002-338583        
However, known methods for producing halogenosilanes and alkoxysilanes, having an alkali-soluble group until now have used multi-step synthesis reactions, and are therefore impractical as methods for low-cost manufacturing.
On the other hand, oxa-silacyclopentanes are known as a cyclic organic silicon compound having a hydroxyl group protected by an organic group (for example in Non-patent Document 1 and Non-patent Document 2).                [Non-patent Document 1] J. Org. Chem. 1997, 62, 4206-4207        [Non-patent Document 2] J. Org. Chem. 2002, 67, 2056-2064        
It is also known that oxa-silacyclopentanes easily ring-opening react by hydrolysis to form a silicon-based resin having an alcoholic hydroxyl group (for example in Non-patent Document 3 and Non-patent Document 4).                [Non-patent Document 3] MakromolekulareChemie 1964, 73, 85        [Non-patent Document 4] MakromolekulareChemie 1966, 97, 241(Organic Silicon Resin Having Alcoholic Hydroxyl Group)        
Various types of organic silicon resins having an alcoholic hydroxyl group are known. The conventional organic silicon resin is one obtained by introducing an alcoholic hydroxyl group into an organic silicon resin constituting a backbone of the polymer.                [Patent Document 1] JP-A-H08-231924        [Patent Document 2] JP-A-H09-176321        [Patent Document 3] JP-A-2001-213963        [Patent Document 4] JP-A-2003-146832        
Since these conventional organic silicon resins are obtained by a polymer reaction whereby a specific reactive group in the polymer is reacted with a compound having an alcoholic hydroxyl group, it is difficult to precisely control an introduced amount of the alcoholic hydroxyl group, and when starting materials remain after the polymer reaction, it is difficult to remove the starting materials and purify an organic silicon resin.
A method whereby an organic silicon resin having an alicyclic epoxide is synthesized, and then an oxidation reaction (polymer reaction) is used to convert the product to an organic silicon resin having a diol has been proposed as a method for obtaining a silicon resin having an alcoholic hydroxyl group (for example in Patent Document 5).                [Patent Document 5] JP-A-H10-87834        
In addition, a polymethylsilsesquioxane-based microparticle having an alcoholic hydroxyl group has been reported (for example in Patent Document 6).                [Patent Document 6] JP-A-H11-116681        
Since an organic silicon resin having an alcoholic hydroxyl group produces an alkali-soluble group, and it is useful as a starting material for lithographic material, organic-inorganic hybrid material and the like.                [Patent Document 7] JP-A-2003-149822        
These resins can also be a starting material for various types of functional materials, since they easily react with a silylating agent.
On the other hand, it has been reported that oxa-silacyclopentanes are useful as intermediates in organic synthesis.                [Non-patent Document 1] J. Org. Chem. 1997, 62, 4206        [Non-patent Document 2] J. Org. Chem. 2002, 67, 2056        
Moreover, basic researches have also been conducted on oxa-silacyclopentane since it easily ring-opening reacts by hydrolysis to give a hydroxyl group.                [Non-patent Document 3] MakromolekulareChemie 1964, 73, 85        [Non-patent Document 4] MakromolekulareChemie 1966, 97, 241        